If they have more than 4*7135 chips the driver will be soldered to the brass pill.

No driver locking ring is supplied so any future upgrades or changes will be harder to perform.

The blueish gray S2+ with the SST40 led and 5A driver has a locking ring.The driver is not soldered in.IMO this is probably the best factory built S2+.It also has a copper mcpcb and bypassed springs.It is often available in the $13-$15 range = best bang for the buck.